/*
 * Copyright (c) 2004-2022, University of Oslo
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the copyright holder nor the names of its contributors 
 * may be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.hisp.dhis.system.util;

import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.reflect.FieldUtils;
import org.apache.commons.lang3.reflect.MethodUtils;
import org.hisp.dhis.translation.Translatable;

/**
 * @author Lars Helge Overland
 */
public class AnnotationUtils {
  /**
   * Returns methods on the given target object which are annotated with the annotation of the given
   * class.
   *
   * @param target the target object.
   * @param annotationType the annotation class type.
   * @return a list of methods annotated with the given annotation.
   */
  public static List<Method> getAnnotatedMethods(
      Object target, Class<? extends Annotation> annotationType) {
    final List<Method> methods = new ArrayList<>();

    if (target == null || annotationType == null) {
      return methods;
    }

    for (Method method : target.getClass().getMethods()) {
      Annotation annotation =
          org.springframework.core.annotation.AnnotationUtils.findAnnotation(
              method, annotationType);

      if (annotation != null) {
        methods.add(method);
      }
    }

    return methods;
  }

  /**
   * Returns Map of fields and their getter methods on the given class and its parents (if any)
   * which are annotated with the annotation of the given annotationType. The annotation can be
   * applied to either field or getter method.
   *
   * @param klass
   * @param annotationType
   * @return Map<Field, Method>
   */
  public static Map<Field, Method> getAnnotatedFields(
      Class<?> klass, Class<? extends Annotation> annotationType) {
    final Map<Field, Method> mapFields = new HashMap<>();

    if (klass == null || annotationType == null) {
      return mapFields;
    }

    FieldUtils.getAllFieldsList(klass)
        .forEach(
            field -> {
              Method getter = ReflectionUtils.findGetterMethod(field.getName(), klass);

              if (getter == null) {
                return;
              }

              if (field.isAnnotationPresent(annotationType)
                  || getter.isAnnotationPresent(annotationType)) {
                mapFields.put(field, getter);
              }
            });

    return mapFields;
  }

  /**
   * Scan through all fields and getters of given class and return those with {@link Translatable}
   * marked. Return Map<String,String> with key is fieldName and value is translation key. This
   * translation key is used for storing translation values in JsonB format.
   */
  public static Map<String, String> getTranslatableAnnotatedFields(Class<?> klass) {
    final Map<String, String> mapFields = new HashMap<>();

    if (klass == null) {
      return mapFields;
    }

    List<Method> methods =
        MethodUtils.getMethodsListWithAnnotation(klass, Translatable.class, true, false);

    methods.forEach(
        method -> {
          Translatable translatableAnnotation = method.getAnnotation(Translatable.class);

          if (translatableAnnotation != null) {
            mapFields.put(
                translatableAnnotation.propertyName(),
                !StringUtils.isEmpty(translatableAnnotation.key())
                    ? translatableAnnotation.key()
                    : translatableAnnotation.propertyName());
          }
        });

    return mapFields;
  }

  /**
   * Check to see if annotation is present on a given Class, take into account class hierarchy.
   *
   * @param klass Class
   * @param annotationType Annotation
   * @return true/false depending on if annotation is present
   */
  public static boolean isAnnotationPresent(
      Class<?> klass, Class<? extends Annotation> annotationType) {
    return org.springframework.core.annotation.AnnotationUtils.findAnnotation(klass, annotationType)
        != null;
  }

  /**
   * Check to see if annotation is present on a given Method, take into account class hierarchy.
   *
   * @param method Method
   * @param annotationType Annotation
   * @return true/false depending on if annotation is present
   */
  public static boolean isAnnotationPresent(
      Method method, Class<? extends Annotation> annotationType) {
    return org.springframework.core.annotation.AnnotationUtils.findAnnotation(
            method, annotationType)
        != null;
  }

  /**
   * Gets annotation on a given Class, takes into account class hierarchy.
   *
   * @param klass Class
   * @param annotationType Annotation
   * @return Annotation instance on Class
   */
  public static <A extends Annotation> A getAnnotation(Class<?> klass, Class<A> annotationType) {
    return org.springframework.core.annotation.AnnotationUtils.findAnnotation(
        klass, annotationType);
  }

  /**
   * Gets annotation on a given Method, takes into account class hierarchy.
   *
   * @param method Method
   * @param annotationType Annotation
   * @return Annotation instance on Method
   */
  public static <A extends Annotation> A getAnnotation(Method method, Class<A> annotationType) {
    return org.springframework.core.annotation.AnnotationUtils.findAnnotation(
        method, annotationType);
  }
}
